CATALOGUE. 281 in a short, included peduncle; perigynia ovate, nerved, tapering to a cylin¬ drical beak, with short teeth; bracts of female spikes evaginate, clasping, or of the empty bract with a vagina 6" long, exceeding the culm; scales 3-nerved, purple, with pale margins and midnerve, the male linear-oblong, acutish, the female lanceolate, tapering to a sharp rough point, longer than the perigynia.—Saguache Creek, Colorado, Wolf (1065). WhUe the culm, leaves, and male spikes in these specimens are fully developed, the female spikes appear to have been arrested in their growth. In the disposition of the spikes, they resemble aristata, but the short teeth of the perigynia exclude them from that species. GRAMINE^. By Geoege Vasey, M. D. Alopecueus aeistulatus, Michx.—Twin Lakes, Colorado, 1873 (1073); Santa Fe, N. Mex., 1874 (32). Varies much in the length of the awn, which is sometimes shorter, sometimes longer than the palet,—sometimes, indeed, as in No. 390, Palmer, 1868, twice as long as the palet, in which case it is hardly to be distinguished from A. geniculatus, L., of which it is consid¬ ered a variety by Steudel There is an equal variation in the stoutness of the culm. Phleum alpinum, L.—Twin Lakes and South Park, Colorado, 1873 (1074). HiLAEiA* CENCHEOiDES, H. B. K.—Culms stolouiferous, 1 foot or less high, frequently rooting at the pubescent nodes; leaves flat, narrowly linear; spike terminal; rachis flattened, flexuous, of 8-10 joints; spikelets in threes, which are connate at the base and alternate on the rachis.—Sanoita Valley, Arizona (595). ViLFA CUSPIDATA, Torr.—Twiu Lakes, Colorado, 1873 (1075, 1076). In some specimens, the glumes are acute and in others obtuse; indeed, *HiLAKiA, H. B. K.—Panicle spike-like, spikelets sessile, in threes, which are connate at the base, the two anterior ones male and from 1- to 3-flowered, the posterior female and 1-flowered. Male flowers: glumes 2, unequal, the lower one bifid and aristate, the upper one emarginate and mucronate; palets linear-oblong, emarginate and rounded at the apex, stamens 3.—Female flowers: glumes 2, opposite, alike, unequally 2-lobed, aristate between the lobes; palets 2, expanded at the base, and abruptly nar¬ rowed into a long neck, inferior one 3-nerved, superior one 2-nerved ; styles 2; grain oblong, compressed, free between the 2 valves.